Two first-half goals from the Swede secured maximum points for Laurent Blanc's side
Zlatan Ibrahimovic completed a flowing move early on to give the Parisians the lead before having a hand in assisting Marquinhos' effort, which followed shortly after. Before half an hour was played the points were secured as the former AC Milan striker found the net once more.
Both sides headed into the game following convincing wins in their opening games against Olympiakos and Anderlecht, but it was the Ligue 1 champions who controlled this clash from start to finish.
Laurent Blanc made four changes to the PSG side that beat Toulouse 2-0 on Saturday, with Alex replacing Zoumana Camara in defence, while Blaise Matuidi, Edinson Cavani and Ezequiel Lavezzi came in for Adrien Rabiot, Jeremy Menez and Lucas Moura.
Nicolas Gaitan and Filip Duricic returned to the Benfica team after being left out of the starting line-up for their 1-1 draw with Belenenses.
It did not take long for PSG to take the lead, as Ibrahimovic opened the scoring after just five minutes. The Swedish striker met Gregory van der Wiel's right-wing cross to tap in to an empty net following an excellent through ball from Matuidi.
Blanc's men continued to dictate the play after breaking the deadlock as they starved Benfica of possession.
Matuidi saw an effort well saved Artur before Ibrahimovic almost forced an opening, but the hosts were eventually rewarded for their dominance with a superb second goal on 25 minutes.
Ibrahimovic was once again heavily involved as the former Barcelona and Milan man skilfully combined with Marco Verratti, who in turn played in Matuidi who pulled back for Marquinhos to find the net from point-blank range.
And the game was all but ended as a contest on the half-hour mark when Ibrahimovic headed Thiago Motta's pinpoint corner past a despairing Artur for his second of the game.
Benfica made one change at the interval as Lazar Markovic replaced Duricic but, although Ezequiel Garay tested Salvatore Sirigu in the early stages of the second half, they struggled to break down the hosts' organised defence.
The chances continued to flow as Miralem Sulejmani drew another save from Sirigu, before Ibrahimovic spurned a chance for a hat-trick, firing over after Artur could only parry substitute Adrien Rabiot's effort.
PSG still attacked as they looked to put the gloss on a wonderful display, with Cavani denied by a superb double save from Artur 16 minutes from time, but by that point the result had long been settled as PSG moved clear at the top of their pool.